The present invention relates to a trimmer for motorboats with a drive mechanism rotatably movably mounted in a gimbal ring by way of horizontal pins, with a revolving part and with a fixed part, of which one part is connected to a pin and the other part is connected to the gimbal ring for rotation therewith.
U.S. Pat. No. 3,834,345 and U.S. Pat. No. 3,641,965 disclose such trimmers, constructed as a rotatable Hall cell and as a rotary potentiometer, respectively, which are attached externally to the gimbal ring, and the revolving part of which is connected to one of the pins for rotation therewith.
This known arrangement of the trimmer requires, in the range of mobility of the gimbal ring rotatable about a vertical axis, special recesses for the trimmer in the protective bubble surrounding the gimbal ring. Due to the externally projecting mounting of the trimmer, there exists, in addition to this additionally occupied amount of space, the danger of damage to the trimmer, especially in case of an extreme rotational position of the gimbal ring where the trimmer in such a case, projects out of the protective bubble.
The present invention is based on the object of arranging a trimmer of the type mentioned in the foregoing so that it is protected from damage and occupies only a small amount of space.
The invention attains this object by providing that the revolving part is connected to the gimbal ring for rotation therewith and is arranged, together with the fixed part within the pin.
By the kinematic reversal of the operation of the trimmer and its arrangement entirely within the pin, no separate structural volume is required for the trimmer. Since the trimmer does not project from the gimbal ring, the danger of damage is eliminated.
According to one embodiment of the present invention the revolving part and the fixed part of the trimmer are arranged in a bore of the pin. This arrangement requires only a small cost in construction, since the bore can be produced in one working step together with the machining of the pin.
For the axial fixation of the trimmer within the bore, a collar, easy to manufacture can be provided, the trimmer being in contact with this collar, and the revolving part penetrating through this collar.
The revolving part can be turned in a constructionally particularly simple way by means of a sleeve attached to the gimbal ring, which sleeve accommodates the revolving part within for rotation therewith and is integral with a plate attached to the gimbal ring. If the plate is arranged to be countersunk and planar with its surface with regard to the gimbal ring, then the trimmer requires no additional space whatever. In contrast thereto, a construction of the trimmer can be produced at lower cost wherein the plate rests on the gimbal ring.
An adjustment of the trimmer is made possible in a constructionally simple way by making the plate adjustable in its rotational position. For this purpose, the plate can be provided, for example, with slotted holes arranged uniformly over the circumference thereof and having the shape of a circular arc section, adjusting screws mounted in the gimbal ring engaging these slotted holes. To protect the trimmer from outside influences, such as seawater, for example, a seal can be arranged on the periphery of the sleeve and in the bore. This seal can be, for example, an O-ring which is held in an annular groove within the bore.
A stable position of the trimmer and additional protection from outside influences are attained in a simple way by casting the fixed part within the pin.
The trimmer, normally being of an electrical or magnetic structure, is connected via supply lines to an indicator instrument. A protected arrangement of these supply lines can be achieved with low structural expenditure by extending the supply lines toward the drive mechanism.